What is a FLIF File Type?
FLIF is a lossless alternative to PNG, WebP, JPEG 2000, JPEG-LS, JPEG XR lossless, MNG, APNG, GIF, and BPG formats and has a better compression rate. It supports RGB, RGBA and grayscale levels with a color depth of 1 to 16 bits per channel.
The FLIF consists of 4 parts.
More information on format is available here.
The first FLIF format was released in October 2015 as an alpha version. In September 2016, the first stable release was released.